1. Field of the Invention
The present invention relates to a working machine, such as a hydraulic shovel (excavator), having an equipment room and a cover member for covering the equipment room.
2. Description of the Background Art
Heretofore, as a construction machine having an equipment room, there has been known one type described in JP 2005-23727 A. This working machine comprises a relatively large guard cover for covering hydraulic equipment. The guard cover is formed with a small window and provided with a small-window cover for selectively opening and closing the small window. The small-window cover is adapted to be strictly lockable by a keylock.
The working machine further comprises a locking mechanism adapted to lock the guard cover in a closed state. The locking mechanism is disposed inward of the small window. This makes it necessary to open the small window and then release a lock function of the locking mechanism, for an opening operation of the guard cover. This allows the locking mechanism to have no complicated structure, such as a key-lock, resulting in an improvement in aesthetic appearance and safety and a reduction in cost of the construction machine.
Meanwhile, working machines include a type having a small turning radius, i.e., an ability to turn in a small radius (small turning type). The small radius of the small turning type restricts an equipment installation space. Consequently, this type of working machine has only a small equipment room, in which there are disposed devices such as a control valve or components connected to the devices such as various valves and pipes or hoses, in closely-spaced relation within the narrow space.
The valves include a specific selector valve which is required to be protected from external shock or the like. In view of the protection, a large distance is preferably given between the selector valve and the guard cover, which reduces a possibility of the shock given to the selector valve when a rock or the like hits against the guard cover so as to deform the guard cover. On the other hand, giving a large distance between the selector valve and the guard cover involves a difficulty of the manual operation of the selector valve from outside of the guard cover.
The problem will be explained more specifically below, with reference to a small turning-type hydraulic shovel 100 shown in FIG. 9 as a reference example.
The hydraulic shovel 100 comprises a lower propelling body 101 (in FIG. 9, a crawler type), and an upper slewing body 102 mounted on the lower propelling body 101. The upper slewing body 102 is equipped with a frame 103 (base frame), an attachment 104, a cab 105, a side cover (guard cover) 107 covering a side equipment room 106, etc. The side equipment room 106 receives therein a hydraulic fluid tank 110, a control valve 111, etc.
As shown in FIGS. 10 to 12, the side cover 107 has a cover body 108 and a small-window cover 112. The cover body 108 has a rear end supported on the side of the frame 103 pivotably about a vertical axis so as to largely and laterally open/close. The cover body 108 has a front end portion formed with an opening 107a, and the small-window cover 112 is attached to the cover body 108 to selectively open and close the opening 107a. The small-window cover 112 is provided with a keylock unit 113 which can be operated by a given key. Inside the side equipment room 106, there is provided a latch member 114, which is adapted to hold the side cover 107 in a closed state and allow a person such as an operator to manually release the holding of the closed state by a simple operation. This means that opening the side cover 107 requires opening the small-window cover 112 and then manually operating the latch member 114 to release the holding of the closed state.
As shown in FIG. 11, the control valve 111 is disposed on a right side of and adjacent to the hydraulic fluid tank 110, extending in an frontward-rearward direction of the hydraulic shovel. The control valve 111 is connected to a large number of pipes (hoses), which are densely provided around the control valve 111; FIG. 11, however, shows only a part of the pipes 111a. 
The hydraulic fluid tank 110 has a front surface, to which a selector-valve bracket 115 is attached. To the selector-valve bracket 115, there is mounted a selector valve 116 adapted to be manually operated to change a flow of hydraulic fluid.
The hydraulic fluid tank 110 has a side surface, onto which a latch bracket 117 is attached. The latch bracket 117 has a generally L shape, having a long strip-shaped arm portion 117a including one end, which is attached to the hydraulic fluid tank 110, and a short latch support portion 117b extending continuously and bendedly from the other end of the arm portion 117a. The latch member 114 is provided on the latch support portion 117b. 
As shown in FIG. 12, the latch member 114 is provided in the middle of an upper region in the opening 107a viewed from a front side thereof, so as to be easily operated. Inside the side cover 107, there is attached a lockable member 118 to the side cover 107; the lockable member 118 is latched by the latch member 114, thus holding the side cover 107 in the closed state. The opening 107a is used not only for the manual operation for the latch member 114 but also for maintenance to be relatively frequently performed, such as the manual operation for the selector valve 116.
In the hydraulic shovel 100, there may be dropped off a rock or the like which has been scooped up during working to thereby hit against the side cover 107. Particularly, the front end of the side cover 107, facing a working area, is likely to be hit. The side cover 107, if largely deformed by the hitting, might transmit the shock due to the hitting to the selector valve 116 through the side cover 107. In view of this, the selector valve 116 is required to be located inwardly far away from the side cover 107 so as to be free from the shock even in the above-mentioned accident. However, the thus located selector valve 116 cannot be easily operated from outside.